now, candidate romney says he opposes any new laws. >> we need a president who will enforce current laws, not create new ones that only serve to burden lawful gun owners. >> reporter: after aurora, mr. obama stressed the need for a ban on assault weapons. so that's a yes. >> a lot of gun owners would agree that ak-47s belong in the hands of soldiers, not in the hands of criminals. >> reporter: the reason obama's yes has an asterisk is that in four years, no new gun control laws have been enacted. in fact, under obama's watch, concealed weapons are now allowed on amtrak trains and in national parks. >> he's continued to pay lip service to those things. but he hasn't shown real leadership in pursuing those changes. >> reporter: yes, background checks have gotten more thorough under obama. where people legally buying guns in gun shops. but the big problem remains gun shows and the internet. specifically, unlicensed dealers selling firearms to buyers with no background check needed. president obama has supported closing the gun show loophole in the past. but the white house says his focus no